DEFECTS IN METALS AND SIMULATION OF MECHANICAL ...

Fig.4-6: Simulatin showing dislocation moving in the direction and joining the
dislocations nucleating under the indenter tip (depth = 7 A). Atoms with a co-ordination
number less than 8 are shown. All other atoms are removed.
Even though the dislocation moved toward the indentation surface and annihilated, we still see a
decrease in the yield load due to the initial presence of the dislocation, which proves that in both
cases either indenting in the direction or the direction the dislocation effect is
pretty much the same, lowering the yield load during nanoindentation.
Fig. 4-7 shows the load displacement curves for all four cases: nanoindentation in the Z direction
without and with dislocation, and nanoindentation in the Y direction with and without a
dislocation.
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